The Kingdom of Back is a historical retelling of Wolfgang Amadeus Mozart’s real-life older sister, Nannerl Mozart, with heavy threads of fantasy. The story follows the young lives of the siblings growing up in a family whose future depends on the recognition of their family talent by the nobility.

Nannerl is at first the gem of the musical Mozart family until the genius other brother seeps out to steal the focus. It seems her talent cannot compete with his innate gift. As she feels more diminished, she turns to the fantasy world they had created. The prince of the Kingdom of Back becomes her focus as she drifts between the realness of the two worlds trying to find her place.

The story unveils itself easily as it follows Nannerl through to adulthood. The symbols and analogies presented in the Kingdom of Back creatively convey the emotion and thought processes of a young adult girl trying to find her way in a world with a domineering father and a child prodigy younger brother. A shift from her adventure-focused fantasy writing, Lu presents the story of a person coming to grips with her future by finding a way to deal with it.